Pharmacists can play an important role in the management of dermatology conditions,
writes Damien O’Brien
Dermatology is the branch of medicine that is concerned with the skin, mucous membranes, hair and nails, and conditions that affect these. Although skin is relatively easy to examine in most cases, there are approximately 1,500 distinct skin diseases and many variants, which can make diagnosis difficult. Observation of the morphology, distribution, configuration, colour, surface and secondary changes of the skin can be useful in the diagnosis and selection of a treatment plan. Studies have shown that about 15% of general practice consultations relate to a skin problem. Some of these may be self-limiting, but others can result in significant disability. Symptoms of skin disease can include itch (localised or general), pain (often stinging or burning) and functional disability but can vary from condition to condition1. There are several conditions that are prominent in dermatology and these are outlined below.
Skin cancer
Skin cancer is the most common cancer in Ireland, with more than 13,000 new cases each year, with this number expected to double by 20402. 90% of skin cancers are caused from ultraviolet (UV) radiation from sun or sunbed exposure. Other risk factors include pale skin, increasing age, smoking tobacco, immunosuppressant medication and immunosuppressant conditions such as human immunodeficiency virus (HIV)2,3. People can reduce their risk of cancer by staying in the shade when the UV index is high, wearing appropriate clothing and wearing broad-spectrum sunscreen that protects against UVA and UVB4.
Classification
There are two main types of skin cancer – melanoma and non-melanoma. Melanoma is a cancer of the melanocytes – cells that make the pigment melanin. Melanoma is much less common than non-melanoma, but it is generally much more serious due to the fact that it can metastasize to other organs in the body. More than 25% of melanoma cases are diagnosed in individuals under 50 years3,5.
Non-melanoma can be further classified into basal-cell carcinoma (BCC) and squamous-cell carcinoma (SCC). BCC originates in cells lining the bottom of the epidermis and accounts for approximately 75% of all skin cancers. SCC originates in cells lining the top of the epidermis and accounts for about 20% of all skin cancers. The prognosis for non-melanoma skin cancer is much better than melanoma skin cancer. BCC does not usually spread to other organs in the body, while there is only a small chance of SCC spreading to other parts of the body, usually the lymph nodes. Non-melanoma skin cancer is more common in older individuals than younger individuals6,7,8.
Symptoms
The first symptom of a melanoma is often a new mole or a change in the appearance of an existing mole. The moles usually are consistent with the mnemonic ABCDE.
Asymmetry: usually asymmetrical with an irregular shape.
Borders: usually an uneven, irregular border.
Colour: usually a mix of colours.
Diameter: usually larger than 6mm.
Evolving / elevated: usually changes over time and usually is elevated above the skin3.
Melanomas can appear anywhere on the body but are much more common in areas that are often exposed to the sun. In rarer cases, they can appear on the eyes, genitals, soles of the feet or palms of the hands. Other symptoms to look out for include swelling, bleeding, pain and itch3.
The first symptom of non-melanoma cancer is usually the appearance of a lump or discoloured patch on the skin, which persists and slowly progresses over months or years. These patches usually develop on skin that has been exposed to the sun. BCC often appears as a small and shiny lump, with a translucent or waxy appearance. It may also look like a red, scaly patch. The lump often grows and may become crusty, bleed or develop into an ulcer. SCC often appears as a firm pink lump with a rough or crusted surface, with some surface scale. The lump is usually tender, bleeds and may also develop into an ulcer6.
Diagnosis
The first step in diagnosing skin cancer is by physical examination and the use of ABCDE mnemonic. Confirmation of diagnosis of skin cancer is generally by biopsy and histopathological examination. A part of the tumour will be removed under anaesthesia and studied under a microscope. Other tests including a computerised tomography (CT) scan, a magnetic resonance imaging (MRI) scan, a positron emission tomography (PET) scan and blood tests may also be performed3.
Treatment
Surgery is the main treatment for both melanoma and non-melanoma skin cancers. The stage of the cancer, the type of the cancer and the patient’s general health all should be considered before selecting a treatment plan. In stage 1 and 2 melanoma and nearly all non-melanoma cancers, surgical excision to remove the cancer and a small area of skin around it is sufficient. A skin graft or a skin flap will be used to cover the excision. Stage 3 melanoma can be detected by a sentinel lymph node biopsy, which will confirm if the melanoma has spread to nearby lymph nodes. The diagnosis is usually confirmed using a needle biopsy and a lymph node dissection or completion lymphadenectomy may be required. Stage 4 melanoma is when the cancer comes back or spreads to other organs3.
Treatment of stage 4 melanoma has improved in recent years, with immunotherapy, targeted treatments and radiotherapy showing encouraging results. Immunotherapy can be used as monotherapy or combination therapy to aid the body’s immune system to kill melanoma cells. Radiotherapy can also be used after surgery to kill cancerous cells. Chemotherapy is rarely used to treat melanoma nowadays, with targeted treatments and immunotherapy the preferred treatment options. Follow-up monitoring should be in place to check for signs of the melanoma returning, to observe for signs of new primary melanoma and to monitor if the melanoma has spread to lymph nodes or other parts of the body3,6.
Psoriasis
Psoriasis is a chronic proliferative and inflammatory condition of the skin, characterised by erythematous plaques that are covered with silver or white scales. It is an immune-mediated inflammatory skin disease, that is often associated with co-morbidities such as psoriatic arthritis, psychological conditions, cardiovascular disease and hepatic disease. The plaques can present anywhere on the body, but the scalp, elbow, knees and lower back are the most common parts of the body. Psoriasis can also affect the joints and eyes – with approximately 10% having eye involvement and nearly one in three patients having psoriatic arthritis. Psoriatic arthritis generally takes five to 10 years to develop after psoriasis is diagnosed 9,10. Psoriasis is relatively common and affects about 2% of the population 11. It can present at any age, but a clear bimodal age of onset has been observed. The mean age of onset for the first wave of diagnosis can range from 15-20 years and a second peak occurring at 55-60 years10.
Pathophysiology
Psoriasis is an autoimmune disease mediated by T lymphocytes, where the exact etiology is unclear. The pathophysiology of psoriasis is multifactorial, with genetics demonstrated to be a primary contributor in patients with early-onset plaque psoriasis. Activated T-cells infiltrate the skin which stimulates proliferation of keratinocytes. Keratinocyte turnover is therefore unregulated which results in the formation of thick plaques. Additionally, the epidermal cells fail to secrete lipids which results in the scaly plaques. Triggers of psoriasis flare-ups include stress, smoking, alcohol and obesity. Certain drugs like lithium, NSAIDs, chloroquine, beta-blockers and steroids can worsen psoriasis. Psoriasis generally improves in the summer and worsens in the winter10,12.
Classification and symptoms
There are several subtypes of psoriasis and each have different symptoms. The different subtypes are outlined below:
Plaque psoriasis – is the most common form of psoriasis and accounts for approximately 90% of cases. It generally presents as red and dry plaques, covered in silver scales. The plaques may be itchy and sore. It can appear on the body but is most often on the elbows, knees, scalp and lower back10,13.
Scalp psoriasis – presents as red patches covered in thick silver / white scales on the scalp. It can cause severe itchiness and sometimes temporary hair loss10,13.
Guttate psoriasis – causes small (less than 1cm) sores, mainly on the chest and back. It is common after a streptococcal infection in children and oftens disappears completely after a few weeks, but individuals can develop plaque psoriasis. It presents as large, smooth and erythematous patches10,13.
Inverse psoriasis (flexural psoriasis) – affects creases in the skin, often in the armpits, under the breasts, groin or buttocks. It is exacerbated by friction and sweating10,13.
Pustular psoriasis – is a rare form of psoriasis that causes pus-filled blisters (pustules) to appear on your skin. These blisters are non-infectious and surrounded by erythema10,13.
Psoriatic arthritis – is a form of inflammatory arthritis which affects approximately one in three of patients with psoriasis. It involves inflammation of the joints and connective tissue in the joints of the fingers and toes. It can also affect the hips, knees and spine10,13.
Erythrodermic psoriasis – is rare but causes inflammation covering more than 90% of the total body area. It is often as a result of abrupt withdrawal of systemic steroids which causes an exacerbation of unstable plaque psoriasis. This leads to symptoms such as sever itch, pain, swelling, burning and can cause complications such as infection, dehydration, hypothermia and heart failure10,13.
Diagnosis
Diagnosis can usually be made by clinical morphology and site of lesions. In some cases, where diagnosis is difficult, biopsy and histopathology are possible. Several laboratory studies may be ordered including a full blood count, hepatic function tests, renal function tests, rheumatoid factor and uric acid levels. Differential diagnosis is required to rule out conditions including eczema, seborrheic dermatitis, mycosis fungoides and secondary syphilis. X-rays or referral to rheumatology may be necessary if psoriatic arthritis is suspected10,14.
Treatment
There are several treatment options available for psoriasis, including topical treatment, systemic treatment and phototherapy. Emollients and moisturisers should be used in most cases as they can help in improving barrier function and hydrating the stratum corneum. Ointments are often preferred as they are thick, greasy and have a longer contact time on the skin 13. Mild to moderate psoriasis can be topically treated with corticosteroids, vitamin D analogues, calcineurin inhibitors and phototherapy. Moderate to severe disease often requires systemic treatment. The presence of co-morbidities, including psoriatic arthritis, also must be taken into consideration15.
Topical
Topical treatments are usually first-line treatments for mild to moderate psoriasis. Corticosteroids have been shown to be effective in treating psoriasis. They reduce inflammation, slow down the production of skin cells and reduce itching. Corticosteroids are classified based on their potency, with low, medium and high potency all potential options. Betamethasone and clobetasol are examples of high-potency corticosteroids, fluticasone and mometasone are medium potency and hydrocortisone is a low-potency corticosteroid. Medium- to high-potency corticosteroids are often used to treat most areas on the body, including the trunk and extremities. They are useful in areas of thick skin, such as plagues 16. Corticosteroids used for the face, genitalia or areas of thin skin should be either avoided or of low potency and limited to short-term use13. Potential adverse effects of topical corticosteroids are usually local and include easy bruising and thinning of the skin. Systemic adverse effects are rarer and could include hypertension, mood swings, weight gain and Cushing’s syndrome16.
Calcineurin inhibitors work by reducing the activity of the immune system and help to reduce inflammation. They are often used to treat sensitive areas or can be used if corticosteroids are ineffective. Tacrolimus is a topical calcineurin inhibitor that is licensed for use in Ireland. Vitamin D analogues can be used alongside or instead of topical corticosteroids. They reduce inflammation and slow production of skin cells and are effective for mild to moderate psoriasis on the trunk, limbs and scalp17. Calcipotriol is the most common vitamin D analogue used in Ireland. Potential adverse effects of calcineurin inhibitors and vitamin D analogues are usually quite mild when used correctly and mainly include local skin irritation or burning, that usually revolves within a week17. The efficacy of topical therapy can be increased with combination therapy or occlusion 13. Calcipotriol and betamethasone are licensed for use as combination therapy and can be used as first-line treatment. This is more effective than monotherapy and improves compliance in chronic psoriasis patients18. In patients that have plagues with significant scale, it may be necessary to use a de-scaling agent prior to commencing therapy, such as coal tar13.
Phototherapy can be used as a second-line treatment. Most patients receive a narrow band UVB, with some receiving UVA through psoralen with ultraviolet A radiation (PUVA). There is a maximum amount of phototherapy a patient can receive in their lifetime to reduce the risk of skin cancer13.
Other treatment options
Systemic drugs can be used if topical treatment fails. Routine blood, liver and renal functions tests should be regularly carried out in patients on systemic therapy. Methotrexate and cyclosporine are examples of possible systemic treatment options for moderate to severe disease 10.
Methotrexate reduces the immune system by inhibiting lymphocytes. It does this via multiple mechanisms – inhibiting dihydrofolate reductase, blocking aminoimidazole carboxamide ribotide transformylase (AICARTase) and adenosine accumulation. Potential adverse effects include bone marrow suppression, nausea, hepatitis and teratogenicity. It is generally administered once weekly. It can be given orally, but subcutaneous injection increases bioavailability and reduces gastrointestinal side effects. Ciclosporin is a calcineurin inhibitor and works by reducing the activity of T-cells. Potential adverse effects include hypertension, arrhythmias, dyslipidaemia, increased risk of infection, increased risk of lymphoma and decreased renal function12,19.
Biologicals are monoclonal antibodies that target pro-inflammatory cytokines and have great effectiveness in reducing symptoms in moderate to severe disease. They exert their mechanism of action in different ways that are outlined below 10 13. Adalimumab, etanercept, infliximab and certolizumab have their effectiveness by inactivating tumour necrosis factor-alpha (TNF?). Ustekinumab works by blocking Interleukin (IL) -12 and IL-23. Secukinumab and tildrakizumab exert their mechanism of action by blocking IL-23 10,13. The choice of biological should be taken by a specialist and tailored to the needs of the patient. This choice is influenced by disease phenotype, outcome of previous biological treatment, co-morbidities, dosing frequency and lifestyle considerations. Biologicals require subcutaneous or intravenous administration, and the patient should be tested for hepatitis and tuberculosis before initiating therapy10,13.
Dermatitis
Dermatitis is a group of itchy inflammatory conditions characterised by epidermal changes. It is a common condition, with approximately 20% of people having the condition at some stage in their lives. Among the most types of dermatitis include atopic dermatitis, contact dermatitis and seborrheic dermatitis. Other types of dermatitis include photosensitive dermatitis, post-traumatic dermatitis, discoid dermatitis, eyelid dermatitis and hand dermatitis20.
Classification
Atopic dermatitis – is also known as eczema and is a common form of dermatitis in both adults and children. It is associated with other immunoglobulin E (IgE) associated conditions like allergic rhinitis, asthma and food allergies. Atopic dermatitis has a complex etiology, which includes both genetic and environmental factors and leads to abnormalities in the epidermis and immune system. Environmental factors including tobacco smoke, air pollutants, certain skin products and certain foods can trigger or exacerbate atopic dermatitis. The most common symptoms of atopic dermatitis are itching, skin redness, dry skin, weeping rash and thickening of the skin. The hands, backs of the knees, insides of the elbows, face and scalp are the most common affected parts of the body. Complications of dermatitis include bacterial infection, viral infections, psychological issues and sleep problems21,22.
Seborrheic dermatitis – is a common skin condition that presents in areas high in sebaceous glands, particularly the scalp, face and body folds. It is caused by a local inflammatory response to fungi colonisation on the skin. Symptoms include itchy, red patches and scales on the skin, with white or yellow flakes on the scalp23.
Contact dermatitis – can be further subcategorised as allergic contact dermatitis and irritant contact dermatitis. Allergic contact dermatitis occurs when an individual is exposed to an allergen that causes a hypersensitive reaction involving the immune system and may be caused by nickel, hair dye, perfumes and rubber. Irritant dermatitis occurs when an individual is exposed to an irritant for a period of time sufficient to damage the outer layer of the skin and may be caused by a wide range of irritants including soap, detergent, shampoo and organic solvents. Symptoms of contact dermatitis includes skin redness, itchiness, burning sensation of the skin, pain and blisters that may be fluid-filled24.
Diagnosis and treatment
A thorough physical examination and a complete medical history is often all that is required for a diagnosis of dermatitis. A range of other investigative tests may sometimes be required for diagnosis. A patch test is useful in identifying contact allergens. Skin scraping and swabbing can be used if a fungal, bacterial or viral infection is suspected. A skin biopsy may be carried out to rule out other conditions. Blood tests can check for an elevation in IgE25,26.
Allergen and irritant identification and avoidance are important in preventing symptoms of dermatitis, with personal protective equipment potentially useful in this regard. Topical therapies are the mainstay in treating dermatitis. The topical treatments that are outlined in the treatment of psoriasis are used to treat dermatitis and these include emollients, corticosteroids, calcineurin inhibitors and phototherapy. Similarly, systemic immunosuppressive and biological therapies that are used in treatment of psoriasis are often used in the treatment of dermatitis, if topical therapy is not fully effective. Antihistamines to suppress the itch associated with dermatitis can be useful. Antibiotic, antiviral or antifungal treatment may be required if an infection is present20.
Role of the pharmacist in dermatology
Pharmacists can play an important role in the management of dermatology conditions. Pharmacists have a good knowledge of dermatological conditions and their treatment. Firstly, community pharmacies are often the first place that patients present with symptoms. Pharmacists can assess the patient and recommend an OTC (over the counter) treatment option if appropriate or refer to a doctor if necessary.
Additionally, pharmacists can contribute to educating patients and improving compliance in patients with skin conditions. The clinical effectiveness of the treatment options is conditioned by compliance to the treatment. Compliance is a major area of concern in treating many chronic conditions, particularly many conditions observed in dermatology. Non-compliance is associated with poor understanding of the dosage instructions. Pharmacists can use their communication skills to educate patients on their condition and the treatment. Pharmacists are the healthcare professionals that have the best skills to educate patients on correct usage of medication, to alleviate concerns and improve compliance27.
References on request
